The present invention relates to non-threaded retainers and more specifically to one-piece molded retainers adapted for use in the assembly of automotive vehicle bodies.
There is a great need in the assembly of automobiles to effect retention of relatively light components throughs the use of non-threaded fasteners which are generally specified to reduce the time required to secure the device for which the retainer is specified. Most of these retainers are formed as injection molded parts having a barbed shank whose diameter exceeds the bounds of the cooperating aperture in the vehicle body into which the fastener is inserted and a head of greater diameter. Retention is effected by inserting the shank into the aperture, deflecting the barbs during insertion and permitting the barbs relaxation into a vacant area This area is typically the other side of the wall in which the aperture is formed. The retainer is configured to define a shank diameter greater than the aperture to resist removal.
A significant disadvantage in using retainers of this sort is that in order to achieve high resistance to pull-out removal of such a retainer, the retaining barbs or other locking device must be sized and shaped in a manner which adds to the resistance in insertion, typically the thickening or angling of barbs of the type shown in U.S. Pat. No. 3,810,279.